US2951327A

US2951327A - Container sealing apparatus

Info

Publication number: US2951327A
Application number: US778811A
Authority: US
Inventors: Frederick E Fauth
Original assignee: Crown Cork and Seal Co Inc
Current assignee: Crown Cork and Seal Co Inc
Priority date: 1958-12-08
Filing date: 1958-12-08
Publication date: 1960-09-06
Anticipated expiration: 1977-09-06

Description

Sept. 6, 1960 Filed Dec. 8, 1958 F. E. FAUTH CONTAINER SEALING APPARATUS 5 sneets-snet 1 INVENTOR'.

ATTORNEYS- Sept. 6, 1960 F. E. FALVITH 2,951,327

CONTAINER SEALING APPARATUS Filed Dec. 8, 1958 5 Sheets-Sheet 2 -:=-h INVENTQR:

66 70 66 F dezjck E.li'auizh,

ATTORNEYS.

Sept. 6, 1960 F. E. FAUTH CONTAINER SEALING APPARATUS 5 Sheets-Sheet 3 Filed Dec. 8, 1958 INVENTORZ E.F aul'h,

Fipedecick W Sept. 6, 1960 F. E. FAUTH v CONTAINER SEALING APPARATUS Filed Dec. 8, 1958 5 Sheets-Sheet 4 INVENTOR Z E ede ckEIjzuth, 4W 1 4/24 W lllll 1| IIL II LhFl ATTORNEYS- Sept. 6, 1960 F. E. FAUTH CONTAINER SEALING APPARATUS 5 Sheets-Sheet 5 Filed Dec. 8, 1958 INVENTOR F dem'ck E 0% MM) ATTORNEYS.

hired rates CONTAINER SEALING APPARATUS Filed Dec. 8, 1958, Ser. No. 778,811

Claims. (Cl. 53-317) The present invention relates to a container sealing apparatus and, more particularly, to an apparatus for applying and securing threaded-type caps upon containers. Although the apparatus and mechanism hereinafter described. is primarily for use in applying. threaded caps of the type having a continuous thread, the mechanism may also be useful in the applicationof the threaded-type caps known as the lug caps or the application of the threaded-type of caps having interrupted threads.

Numerous machines heretofore have been proposed for the securing of threaded caps to containers but such prior machines do not operate efiiciently in the handling of containers moving at high speed, especially where caps containing an uninterrupted or continuous thread are to be received by a container having a mouth provided with uninterrupted or continuous threads. In this respect, a particular difiiculty encountered has been in accurately positioning the cap with respect to the container after it has been picked up by the container but prior to the threading of the cap onto the container mouth. The angle at which the cap must be held with respect to the container mouth is of prime importance when the cap is initially threaded onto the container because, if the cap is in such a position that the threads of the cap and the container do not accurately mate with one another, the cap will be cross-threaded onto the container, resulting. in an improperly capped and sealed container. Such a condition results in amaterial loss of time and product being packaged.

In. the prior United Statesv Patent No. 2,734,672, issued February 14, 1956 to Carl L. Day and Frederick E. Fauth, a container sealing apparatus is disclosed wherein threaded types of caps, such as the continuous threaded cap or the lug cap or interrupted threaded type of cap is applied to containers while the containers are continuously advancing upon a conveyor. In. the aforementioned Day et al. patent the container, withv the loosely applied cap, first passes through a pair of unthreading rollers which, because of their tapered. surfaces, permit. the cap to drop onto the container in the proper oriented position with respect to the threads of the container. The container and cap then pass through a pair of threading rollers which tighten the cap onto the container. The present invention is an improvement over the structure disclosed in the aforementioned Day and Fauth patent for leveling the cap and threading the same onto the container, but it must be mentioned that certain details of description of applicable structure and steps and operation which appear in the above-mentioned Day et al. patent, is not repeated herein, it being understood that the patent is referred to as disclosing structure which would be used with the present invention, and to that extent it forms a part of the present disclosure.

Throughout the. specification and claims the term threaded-type cap will be used and it is understood that such. a term is suthciently broad enough to cover any type of threaded cap, for. example, the continuous threaded- 2,951,327. Patented Sept. 6, 1960 cap, the interrupted threaded-cap, or the lug-type threaded cap. 7

An object of the present invention is to provide an apparatus for securing threaded-type caps to containers, the apparatus being of such design that a cap loosely positioned at random on the container mouth may be readily and firmly secured upon the container 'to thereby close and seal the same.

Another object of the present invention is to provide an apparatus of the type described, wherein the caps loosely positioned at random upon the containers are subsequently oriented to a particular angular relationship with respect to the container mouth, whereby they can then be accurately and quickly threaded upon the container without the danger or the disadvantage of the caps becoming cocked and improperly threaded upon the container.

Still another object of the present invention is to provide a mechanism for leveling the caps with respect to the mouth of the container just prior to the operation of threading the caps onto the containers.v

A further object of the present invention is to provide a mechanism wherein the caps loosely applied upon a container are initially supported above the container mouth to the extent that the threads of the cap are out of engagement with the threads of the container but the skirt of the cap still overlaps the container mouth so that the cap can be moved with the container in a line as the container moves forward through the cap-applying and securing machine.

Still another object of the present invention is to provide a mechanism which will enable a cap-applying and securing machine, of the character described, to operate at higher speeds on containers and caps while the caps and containers are moving in a line rapidly through the machine.

These and other objects and advantages of the present invention will be more apparent from the following specification, claims, and accompanying drawings, in which:

Figure 1 is a fragmentary side elevational view of the cap-applying and securing mechanism of the present invention, portions of the machine being omitted for purposes of clarity.

Figure 2 is a plan view of the structure shown in Figure 1, some of the portions being shown in section.

Figure 3 is an end elevational view of the cap-applying mechanism of the present invention, looking from the left of Figures 1 or 2, and showing the threading rollers in the position assumed just prior to receiving a cap.

Figure 4 is an enlarged. fragmentary sidev elevational view of the cap-leveling unit of the present invention, portions of the unit being broken away and shown in section.

Figure 5 is a top plan view of the cap-leveling unit shown. in Figure 4.

Figure 6 is an end elevational view of the leveling unit shown in Figure. 4, the view being taken. from the left of Figure 4.

Figure 7 is an end elevational view similar to Figure 6 but taken from the right of Figure 4.

Figure 8 is a schematic View showing a cap being initially applied loosely to a container.

Figure 9 is a. view showing a cap loosely applied to the container but level with respect to the container, the cap and the container just coming under the influence of the threading rollers.

Figure 10 is a view similar to Figure 9, but showing the cap being threaded. onto the container by the threadingv rollers, the cap being maintained level by the cap leveling unit as the cap is being threaded onto the container.

'3 Figure 11 is an enlarged fragmentary sectional view taken on the line 1111 of Figure 2.

General description The construction and operation of the machine illustrated in the application, as embodying the invention generally, may be described as followsi Referring to the drawings, and in particular to Figures 1 and 2, the machine of the present invention includes a base casing or housing having an upper surface or worktable 12 across which the top run of a straight-line endless conveyor 14 moves filled jars I, or other containers, from the left to the right in Figures 1 and 2. The containers I first will move through a steam tunnel, such as shown in the aforementioned Day et al. Patent No. 2,734,672 or a nitrogen tunnel, such as shown in the Day et al. Patent No. 2,763,107, issued September 18, 1956. By moving the containers through either a steam tunnel or a tunnel filled with inert gas, such as nitrogen, the head space of the container is displaced of air by either the steam or inert gas prior to the application of a cap C.

After the container J has passed through a desired tunnel and the head space has been purged of air, the container passes under a cap-applying mechanism, generally designated by the numeral 16, the cap-applying mechanism being of the type wherein the cap C is positioned in the path of the moving container I so that it may be picked off by the mouth of the container and loosely positioned thereon. The cap-applying mechanism, which is situated at the discharge end of a cap supply chute 18 receiving properly oriented caps from a hopper (not shown), is of the type disclosed in the aforementioned Day et al. Patent No. 2,734,672, or it may be some other similar and suitable mechanism for loosely applying the caps C to the containers J.

After the cap C has been picked off and loosely applied to the container 1, the container and the loosely applied cap advance on the conveyor 14 to the cap-securing mechanism, generally designated by the numeral 20. The cap-securing mechanism 20 includes a first pair of rotatable members or rollers 22 and 22' positioned above and on either side of the path of the container I and cap C. The rotatable members 22 and 22' are driven in a cap-threading direction and engage opposite sides of the cap and thread the same onto the container I. The cap-securing mechanism 20 also includes a second pair of rotatable members or rollers 24 and 24' positioned above the conveyor 12 and in the path of the cap C after it has been threaded onto the container 1. The members or rollers 24 rotate in the same threading direction and provide means for giving the cap an additional twist to make sure that the cap has firmly threaded upon and seated against the container mouth.. Intermediate the cap-threading rollers 22 and 22' and 2-4 and 24' and extending from a position adjacent the cap-applying mechanism 16, is a cap-leveling unit 26 which accurately positions the loosely applied cap with respect to the mouth of the container so that when the cap-threading rollers 22 engage the cap and move it in a threading direction, the cap will thread properly on the container C. The cap-leveling unit 26 not only holds the cap C level above the container I, but at the proper time, lowers the cap while still maintaining it level, so thatthe cap can be threaded upon the container. A more detailed description of the cap-leveling unit 26 and its cooperation with the cap threading and tightening rollers 22 and 24 respectively, will follow later in this specification.

A pair of opposed endless belts 28, best shown in Figures 1, 2, 9 and 10, are adapted to engage the sides of the container I and hold the container against rotation as the container passes beneath the cap-applying mechanism 16 and the cap-securing mechanism 20. The endless belts 28 are disclosed in detail in the aforementioned Day and Fauth Patent No. 2,734,672 and, therefore,

.4 it will suffice to say that the inner run of each of the belts are merely driven in the same direction as the conveyor 14 and at approximately the same linear speed.

After the container I has had the cap C applied by the cap-applying mechanism 16 and then secured by the threading rollers 22 and 22' and the tightening rollers 24 and 24, the container I is then passed through a subsequent tunnel filled with either nitrogen or steam and then conveyed therefrom to a labeling machine or to a machine for packaging the same. It may be desirable to completely shroud the cap-applying mechanism 16 and the cap-securing mechanism 20 in a tunnel or chest which is supplied with steam or inert gas, as desired. Such a tunnel or chest is'disclosed in the aforementioned Day et al. Patent No. 2,734,672 or No. 2,763,107. By providing a tunnel or chest around the cap-applying mechanism 16 and the cap-securing mechanism 20, it is insured that no air enters the head space of the container after the head space is initially purged and during the capapplying and securing operation.

Cap-securing mechanism Referring specifically to Figures 1, 2 and 3, the capsecuring mechanism 20 is supported within a superstructure, generally designated by the numeral 30, the superstructure being carried by suitable posts (not shown) above the worktable 12. In more detail, the superstructure 30 is provided with horizontally extending

bars

32 and 34 which are arranged above the horizontal conveyor 13 and which support the housings 36 and 36', as well as the housings 38, a portion of one being shown in Figure 1. As fully disclosed in the aforementioned Day et al. Patent No. 2,734,672, the superstructure 30 may be raised and lowered vertically with respect to the conveyor 14 so that the cap-securing mechanism 20 may be adapted for containers of different heights.

The housings 38, which are situated on opposite sides of the conveyor 14 and above the same, provide a means for supporting drive shafts (not shown) for each of the endless belts 28. The arrangement for driving the belts 28 is substantially identical with that disclosed in the aforementioned Day et al. Patent No. 2,734,672 and, therefore, further description herein is unnecessary. In this respect, it should be added that the source of power for driving endless belts 28, conveyor 14 and tightening rollers 24 and 24' is located in the base 10 and is transferred to the various units by chain drives, sprockets, gears and the like, such as shown in the aforementioned Day et al. Patent No. 2,734,672.

As best shown in Figures 2 and 3, the housings 36 and 36' are supported above the endless conveyor 14 and on opposite sides of the same by the horizontal bar .32. Since the elements of the inner housing 36' are substantially identical to the elements of the outer housing 36, the description will refer only to the outer housing 36 and its associated elements, it being understood that the parts of the inner housing are given primed reference numerals.

The housings 36 and 36' support the threading

rollers

22 and 22 and 24 and 24', as will be hereinafter described. Referring to Figure l, a splined drive shaft 40 extends transversely between the housings 36 and 36'. As previously mentioned, the splined drive shaft 40 is driven by the same source of power which drives the conveyor 14 and endless belts 28 and as disclosed in the aforementioned Day et al. Patent No. 2,734,672. As schematically shown in Figure 1, a gear 42 in housing 36 is slidalble upon or keyed to the shaft 40, a similar such gear 'being provided in the housing 36. The gear 42 meshes with a spiral gear 44 fixed on a vertical shaft 46 provided in a chamber 47 (Figure 11) in the housing 36. The upper end of shaft 46 is journaled, as indicated at 48, beneath a cap plate 50, whereas, the lower end extends from beneath the housing through a bearing 52,

all

as best shown in Figure 11. The bearing 52 has a collar 54 secured to its outer raceway, the collar 54 serving as a pivot for a carrier member 56, which is best illustrated in Figures 1 and 2 as a horizontally arranged plate extending toward the infeed end of the machine, the free end portion of the plate, as hereinafter described, being adapted to support the threading roller 22.

Arranged immediately beneath the carrier member 56 and welded to the end of shaft 46, as indicated at 58, is a gear member 66 having peripheral teeth 62. When the shaft 46 is rotated by the rotation of drive shaft 40, gear member 60 will rotate and will transmit motion, as will be subsequently described, to the threading roller 22. Carried on the end of shaft 46 for rotation with the shaft 46, is the tightening roller 24. As best shown in Figure 1, the tightening roller 24 is provided with a bearing 64, shown in dotted lines, so that it may rotate relative to the shaft, if an overload is applied thereto. In other words, a slip clutch arrangement (not shown) may be provided between the roller 24 and the gear 60 so that normally the roller 24 is rotated with the gear 60. However, should -a load be applied to the tightening roller 24 above a normal load, the shaft 46 will be able to rotate with the gear 60, while the clutch mechanism provides for slippage of the roller 24.

The tightening rollers 24 and 24 are provided with peripheral surfaces made of rubber or other suitable resilient but relatively rigid material which is adapted to grip the cap after it is threaded onto the container and to give it a final twist so that a tight seal is insured. Adjustment of the tension on the slip clutch (not shown) determines the tightness with which cap C is finally threaded onto the container I.

As mentioned above, the tightening roller 24' carried by the inner housing 36' is mounted identically to, and driven in the same manner, as the above-described mounting of the roller 24. Both the rollers 24 and 24' rotate in the direction of the arrows in Figure 2 so that a cap threading and tightening movement is imparted to the cap, while the container is prevented from rotating by the opposed belts 28.

Referring now to Figure 11, it will be noted that the plate or carrier member 56 is supported for pivotal movement about the collar 54 by means of a ring bearing, generally designated by the numeral 66. The ring bearing 66 is held in place by means of the

studs

68 and 70 which are threaded into the plate 56 and collar 54 respectively. The threading rollers 22 and 22' are journaled on the forward end of plates 56 and 56' and are each provided with a gear 72 and 72' positioned immediately below the

plates

56 and 56. Also journaled to the plates 56 and 56', as indicated at 74 and 74' respectively, are idler gears 76 and 76'. The gears 76 and 76' each mesh with the teeth of the gears 60 and 60' respectively, and the

gears

72 and 72 respectively. Thus, it is obvious from Figure 2 that when the tightening rollers 24 and 2.4. are driven by the shaft 46, the gears 60 and 60' will transmit motion to the gears 76 and 76' which will in turn transmit motion to the

gears

72 and 72, in the same direction as the gears 60 and 60'. When the gears 72 and 72' are rotated in the same direction as the gears 60 and 60', the threading

rollers

22 and 22 are driven in the same direction or in other words, a direction to cause a threading motion to the cap loosely applied to the container.

Since the threading rollers 22 and 22' serve the purpose of threading the cap on the container and thus require more rotations of the cap with respect to the container than do the rollers 24 and 24', the gear ratio between the

gears

72 and 72' and 60 and 60- is such that the gears 72 and 72' are rotated at a higher r.p.rn. than the. gears 60 and 60. This is accomplished by making the gears 72 and 72' of less diameter than the

gears

60 and 60.

It will be noted from Figures 1 and 3 that the thick ness of the rollers 22 and 22' is greater than the thick- 8 new of the. rollers 24 and 24' and the reason for this is that the cap C must travel vertically downwardly further when it is in contact with the rollers 22 and 22' than when it is merely being twisted to prow'de the final tightening, such as accomplished by the rollers 24 and 24. In order that there is no interference between the bead C provided on the skirt of the usual threaded cap and the roller 22, the lower edge of the

rollers

22 and 22 are beveled, as indicated at 78 and 78'. Rollers 22 and 22' have their peripheral surfaces made of rubber or other suitable resilient, but relatively rigid, material so that they can obtain a good grip on the cap.

A post 80, extending vertically upwardly from the carrier 56, is provided with a reduced section 82 which is adapted to receive one end of a tension spring 84. The other end of tension spring 84 is adapted to hook into a clip member 86 secured to the housing 36 by means of a stud 88. Referring to Figures 2 and 3, it will be seen that the

springs

84 and 84 tend to cause the carrier members 56 and 56' respectively, to pivot about the collars 54 toward the longitudinal axis of the conveyor 14. Such movement will bring the rollers 22 and 22' closer together than the diameter of a cap C, and such inward movement of the

rollers

22 and 22 is controlled by means of stop members 90 and 90' provided in

upstanding lugs

92 and 92 carried on top of the

carrier members

56 and 56, respectively. In more detail, and referring just to the lug 92, it will be noted that it is provided with a cut-out portion 94 which is adapted to slide over the horizontal bar 32. The stop member 90 includes a stud threaded into the lug 92 and adapted to limit the inward movement toward the center of conveyor 14 of the plate members 56 by abutting the bar 32. When the plate or

carrier members

56 and 56 are pivoted apart from one another, the

lugs

92 and 92 slide forward with respect to the horizontal bar 32.

Referring now to Figures 1, 2, 4, 5, 6 and 7, the capleveling unit 26 is positioned above conveyor 14 and is rigidly supported by the horizontal cross bar 32. In more detail, the cap leveling unit includes an elongated leveling bar body 96 which is provided at its rear end with a cut-out portion 98 adapted to receive the bar 32. Any suitable means may be provided for rigidly holding the body 96 to the bar 32, such as the stud 100 extending through the bar and threaded into the body.

As shown in Figure l, the body 96 extends from a position just over the end of the cap-applying mechanism 16 to a position 102 just to the rear of the forward pair of threading rollers 22 and 22'. The undersurface of the bodymember 96 is tapered, as indicated at. 104, on an angle substantially equal to the angle which the cap C rests in the cap-applying mechanism 16 just prior to its being picked off by a container C. From a position 106, just forward of the threading

rollers

22 and 22, the cap-engaging surface 108 of body 96 is parallel to the conveyor 14 and thus, when a cap is in engagement therewith it will be maintained level with respect to the container I. Since the body 96 does not move vertically with respect to the container 1 or to the conveyor 14, but is rigidly fixed to the bar 32 of superstructure 30, means are. provided for supporting the cap C flush against the undersurface of the body 96 so that the undersurface provides a guide for the cap. As shown in Figures 4 and 5 a plurality of longitudinally arranged

permanent magnets

110 and 112 are supported in recesses 114 provided in the undersurface of body 96. Thus, when a cap C is picked off of the cap-applying mechanism 16 by av container traveling on the conveyor 14 between the belts 28, the cap will follow the contour of the undersurface 108 of body 96, as the magnets will immediately support the cap flush against the surface 108. It will be explained in more detail the importance of maintaining the cap in this supported position as the container and the loosely applied cap are being transferred in a line through the capsecuring mechanism.

The cap-leveling bar body 96 is provided'on 'its' upper surface with a pair of upstanding walls 116, each of the walls being provided with a dovetail vertically extending recess 118. A cap slide assembly 120, including a pair of spaced cap slides 122 and 124 connected together by a block member 126, is adapted to be received in the dovetail recesses 118 provided in the cap-leveling bar body 96. As shown in Figures 6 and 7, the cap slides 122 and 124 are each provided with a trailing portion 128 which extends rearwardly to the trailing end 102 of the cap-leveling bar body 96, the rearwardly trailing portion 128 being received in a recess 130 provided in the body 96. It is now evident that the cap slide assembly 120 is capable of vertical movement with'respect to the leveling bar body 96 and that its lower capengaging surface 132 of each of its

slides

122 and 124 can engage a cap in contact with the leveling bar body 96 and move the same vertically downwardly.

To effect the vertical movement of the cap slide assembly 120, an L-shaped bracket 134 is bolted to the block member 126, as indicated at 136. The bracket 134 is provided with a horizontally extending portion 138 having a recess or counterbore 140 in its upper surface. The recess 140 is adapted to receive the lower end of a compression spring 142, the upper end of the spring being received on a stud 144 carried on an arm 146 bolted, as indicated at 147, to a block 148 provided on the housing 36. The block 148 is bolted to the housing, as indicated at 150.

A similar block 152 is bolted to the housing 36', as indicated at 154 in Figure 2. The

blocks

148 and 152 support horizontally extending

pins

156 and 158 respectively, the pins extending forwardly of the cap-securing mechanism 20 on either side of conveyor 14 and above the cap-threading rollers 22 anw 22'. Pivotally mounted on each of the

pins

156 and 158 are bell-

cranks

160 and 162, respectively. One arm of each of the bell-cranks engage the undersurface 164 of the horizontal portion 138 of bracket 134, whereas, the other arms of the

bellcranks

160 and 162 engage the heads 166 and 168 of

studs

170 and 172 respectively. The

studs

170 and 172 are threadedly carried in

upstanding lugs

174 and 175 carried respectively by the

carrier members

56 and 56. The

lugs

174 and 175 may either be permanently welded to the plates or bolted, as shown at 176 and 177 in Figure 3. As is now evident, when the carrier members 56 and 56' are moved apart by a cap passing between the rollers 22 and 22', the heads 166 and 168 of the

studs

170 and 172 respectively, will be withdrawn from engagement with the arms of bell-

cranks

160 and 162. The spring 142 extending between the fixed member or arm 146 and the bracket 134 of slide unit 120 will cause the slide unit to move downwardly and the two

slides

122 and 124 will move down simultaneously and cause the cap spinning between the

rollers

22 and 22 to move downwardly toward the container where its threads engage the threads of the container and it is threaded thereon. 4 1

As soon as the cap has been threaded onto the container and the container has moved the cap out of infiuence of the rollers 22 and 22', the carriers 56 and 56' are caused to move toward one another by the springs 84 and 84' and, this in turn, will cause the bell-

cranks

160 and 162 to move in such a direction as to lift the slide assembly 126 vertically upwardly, compressing the spring 142. It should be understood that the cumulative forces of the springs 84 and 84' must be greater than the force of spring 142 in order that the cap slide unit 120 can be raised.

Operation The operation of the container sealing apparatus of the present invention may be best described by referring to the diagrammatically illustrated views of Figures 8, 9 and 10. Assuming that a cap C, made of paraskirt of the cap C, when in the position to be picked off of-the'cap-applying mechanism 16 by the container J, is positioned a distance above conveyor 14 slightly less than the total height of the container. As the container moves from the left to the right of Figure l, the cap C slides out from under the influence of the cap-applying mechanism 16 and is carried loosely by the container under the leveling bar body 96 of the cap leveling unit As soon as the cap C has been picked oft of the capapplying mechanism 16, it will enter the magnetic field of the longitudinally aligned magnets and 112. This causes the cap to be attracted to the body 96 and its top surface to follow closely the lower cap-engaging surfaces 104 and'108 of the body. After the cap has passed the position indicated by the numeral 106 it will level out and will be supported horizontally above the container I so that the threads of the cap are out of engagement with the threads on the mouth of the container I. Figure .3 shows the cap, in dotted lines, supported in this position just prior to the cap passing between the rollers 22 and 22'. Figure 9 illustrates the cap passing

betweenthe rollers

22 and 22 and it is important to note that the mouth of the container J is still surrounded by the lower edge of the cap so that it can still engage the lower edge of the cap and drag it along the cap leveling bar body 96.

, When the cap and the container pass between the

rollers

22 and 22, the cap will cause the rollers and their carriers 56 and 56' to pivot outwardly from a position shown in Figure 3 to the position shown in Figure 9.. This outward movement of the rollers causes the cap to be lowered downwardly onto the muth of the container where the cap threads will engage the threads on the container and the cap will be screwed on the same. It may be pointed out at this time that as soon as the cap C, being moved horizontally by the container J, engages the

rollers

22 and 22 it begins to rotate in a threading direction. However, because the cap C is supported by the magnets of the bar body 96 a sufiicient distance above the mouth of the container J, threading action of the cap onto the container does not commence as the threads of the cap and the threads of the container are not in mesh with each other. Continued movement of the cap andthe container in the direction to cause further sepaeration of the

rollers

22 and 22, as shown in Figure 9, will cause the

carrier members

56 and 56 to pivot away from each other, whereby the heads 166 and 168 of the

studs

170 and 172 respectively are withdrawn from engagement with the bell-cranks and 162. Referring to Figure 3, when the studs and 172 are moved away from each other it will be obvious that the bell-crank 160 can move in a counterclockwise direction, whereas, the bell-crank 162 can move inua clockwise direction. Since the ends of the bell-

cranks

160 and 162 support the cap slide assembly 120 in its upper position, the movement of the ends of the bell-crank away from the underneath surface of the bracket 134 will permit the spring 142 to urge the cap slide assembly 120 vertically downwardly, as shown in the dotted lines in Figure 3 and in the full lines in Figure 10. Movement of the slide assembly 120 vertically downwardly will urge the cap, while maintaining it level, downwardly upon the container until the threads of the cap come into engagementw-ith the threads on the mouth of the container. The continued rotation of

rollers

22 and 22 will quickly thread the cap onto the container. The above described operation of threading the cap onto the mouth of, the container takes place while the container is still moving forwardly on the conveyor 14, it being understood that the container is maintained against rotation by means of the opposed belts 28.

After the cap has been threaded onto the container and the container is moved out of influence of the

rollers

22 and 22 the springs 84 and 84' will urge the carrier members 56 and 56' back to the position shown in Figure 2, wherein the bell-cranks are moved to a position where they support the cap slide assembly 120 in its upper vertical position so that the lower cap-engaging surfaces 132 are flush with the cap-engaging surface 168 of the leveling bar body 96. The container and the threaded cap then pass between the tightening rollers 24 and 24 which are on fixed centers and spaced apart a sufficient distance to merely engage the. periphery of the cap. The cap tightening rollers 24 and 24' give the cap an added twist to insure that the cap. is tightly sealed onto the container with the proper torque. As mentioned above, the rollers 24 and 24 are provided with a clutch mechanism which will permit them to slip when the cap is sufiiciently tight on the container.

The cap securing mechanism of the present invention has advantages over those heretofore proposed, in that it provides a fast, efficient and accurate means of threading a cap, such as a continuous thread cap, on a container having a mouth with a continuous thread. Such caps and containers require a much closer control when the caps are being applied and secured, as the threads must not be crossed. Although the present invention is particularly adapted for use with the caps having continuous threads, it will be apparent that other types of threaded caps, such as the lug cap or the interrupted threaded cap, may be used without departing from the scope of the invention. In accomplishing the desired results, the present invention contemplates maintaining the cap leveling bar body 96 at. a fixed height above the conveyor 14 and container I so that the caps and the containers will always have the same relative position to one another just prior to the threading operation. Such a fixed arrangement of body 96 prevents one cap from having an influence on another cap. Stated another way, should a cap become cocked with respect to the container or to the body 96, the cap will have no influence on adjacent caps which would occur if the body 96 were resiliently mounted. This becomes more apparent when it is realized that the cap sliding assembly 120 is arranged to act on one cap at a time. By providing the cap slide assembly 120 adjacent the cap-threading rollers so that the cap can be lowered while it is rotating, enables the cap to be threaded onto the container without the danger of the threads being crossed.

Having set forth the nature, objects and advantages of the invention, it-will now be perceived and obvious, that the invention is susceptible to some changes, adjustments and modifications, without departing from the principle and spirit thereof. For this reason the terminology used in the specification is for the purpose of description and not of limitation, the scope of the invention being indicated in the claims.

I claim:

1. In a mechanism to secure a cap element provided with threaded-type engaging means to a threaded-type container element mouth: means to move the container element and a loosely applied cap element in a predetermined path; means to support said cap element in a predetermined angular position with respect to and at a fixed vertical position above said container element with threads of said cap element out of engagement with threads of said container element; cap tightening means arranged to engage opposite sides of the cap element and turn it in a cap-threading direction; and means movable with respect to said cap supporting means and operable by said cap-threading means when said capthreading means engages a cap element, said last men- 10 tioned means engaging the cap element and urging the same away from said cap supporting means toward said container element whereby the threaded portion of said cap element engages the threaded mouth and is threaded onto said container element.

2. A mechanism of the character described in claim 1 wherein said cap tightening means includes a pair of rotatable members positioned on each side of said path to engage the periphery of the cap-element, said pair of rotatable members being yieldably mounted and having their cap-engaging peripheries spaced apart a distance less than the diameter of a cap element.

3. A mechanism of the character described in claim 1 wherein said cap tightening means includes a pair of rotatable members yieldably mounted on each side of said path, said rotatable members being urged apart. by' a cap element and thereby causing operation of said means for urging the cap element away from said cap-supporting means.

4. A mechanism of the character described in claim 3 wherein said means urging. said cap element away from said cap-supporting means. includes a member engaging a cap element on its top to move the, same axially toward said container element.

5. A mechanism of the character described in claim 4 wherein said cap-engaging member is resiliently urged toward said container element when said rotatable members are urged apart.

6. In a mechanism to secure a cap provided with a threaded-type engaging means to a threaded-type container mouth: a supporting frame; a container supporting conveyor beneath said frame to move in a straight line containers having caps loosely applied thereto; a pair of cap-engaging rollers journaled on said frame on opposite sides of said conveyor to engage opposite sides of a cap and turn it in a cap-threading direction; a cap leveling means positioned above said conveyor and fixed relative said frame, said cap leveling means having a cap-engaging surface with at least a portion parallel to said conveyor, said cap leveling means including means to support a cap carried by a container in a position where the threaded portion of the cap is out of engagement with the threaded portion of the container; and vertically movable means positioned adjacent and intermediate said cap-threading rollers for engaging the cap top and moving the same away from said cap-supporting means. to a. position where the. cap-threading rollers cause the cap to be threaded onto the container mouth.

7. A mechanism of the character described in claim 6 wherein said leveling means includes a member extending longitudinally above said conveyor from a position forward of said cap-engaging rollers to a position at least adjacent the same.

8. A mechanism of the character described in claim 6 wherein said means for supporting a cap on said leveling means includes magnetic inserts spaced longitudinally of said leveling means.

9. A mechanism of the character described in claim 8 wherein said magnetic inserts are permanent magnets.

10. A mechanism of the character described in claim 6 wherein said means for engaging the cap top and moving the same away fromsaid cap-supporting means includes a member carried by said leveling means and movable axially with respect to a container.

11. A mechanism of the character described in claim 10 including means operatively connecting said cap topengaging member to said cap-engaging rollers whereby said cap top-engaging member is actuated when a cap is engaged by said rollers.

12. A mechanism of the character described in claim 10 wherein said member engaging the cap top includes a pair of parallel elements aligned in parallel relationship with the axis of said conveyor and adapted to engage the cap top at spaced points.

13. In a mechanism to secure a cap provided with threaded-type engaging, means to a threaded-type container mouth: a supporting frame; a container-supporting conveyor beneath said frame to move in a straight line containers having caps loosely applied thereto; a pair of cap-engaging rollers journaled on said frame on opposite sides of said conveyor to engage opposite sides of a cap and turn it in a cap-threading direction, said cap-engaging rollers being normally urged toward each other to a position where said rollers are spaced apart a distance less than the diameter of a cap; a cap leveling member positioned above saidconveyor and extending from a position forward of said cap-engaging rollers to. a position at least intermediate said cap-engaging rollers; magnetic means carried by said cap leveling member for supporting a cap loosely applied to a container at a fixed vertical position above the container with the threads of the cap out of engagement with the threads of the container; a cap top-engaging member movable toward said conveyor, said cap top-engaging member being urged to move a cap away from said magnetic means on said leveling member axially toward said container when said cap is engaged by said cap-engaging rollers to thereby permit said cap to be threaded onto said container.

14. A mechanism of the character described in claim 13 wherein said cap top-engaging member is operatively connected to said cap-engaging rollers and is adapted to move toward said conveyor when a cap loosely applied to a container urges said cap-engaging rollers apart.

15. A mechanism of the character described in claim 14 wherein said cap top-engaging member is resiliently urged toward said container and wherein said cap topengaging member is positively withdrawn away from said conveyor when said cap-engaging rollers are urged toward each other.

16. In a mechanism to secure a cap provided with a threaded-type engaging means to a threaded-type container mouth: a supporting frame; a container-supporting conveyor beneath said frame to move in a straight line containers having caps loosely applied thereto; a pair of cap-engaging rollers on opposite sides of said conveyor to engage opposite sides of a cap and turn it in a threading direction; means to support said cap-engaging rollers on said supporting frame wherein said rollers have movement toward and away from each other, said support means including plate members for journaling each of said rollers,v said plate members being pivotally connected to said supporting frame aft of said rollers; a cap-leveling member positioned centrally of said rollers and extending forward of the same; means carried by said leveling member to support a cap above a container with its threads out of engagement with the threads on the mouth of the container; and means carried by said leveling member adjacent said rollers for movement with respect to said leveling member to urge a cap away from said leveling member toward said container when the cap and container are between said rollers whereby said rollers can thread the cap onto the container.

17. A mechanism of the character described in claim l6'including resilient means normally urging said rollers toward one another and means controlled by movement of said rollers toward one another for operating said gieans for urging the cap away from said leveling mem- 18. A mechanism of the character described in claim 16 wherein said means for urging the cap away from said leveling member includes a shoe member spring-urged toward said cap member when said rollers are engaged by and moved apart by a cap, said shoe member including a pair of parallel plate elements each having a cap-engaging surfaee for engaging a cap simultaneously at spaced points and lowering the same with respect to said leveling member.

19. A mechanism of the character described in claim 16 wherein said means to urge a cap away from said leveling member includes a shoe member movable vertically with respect to said leveling member and means for moving said shoe member when said cap-engaging rollers are moved toward and away from each other.

20. A mechanism of the character described in claim 19 wherein said last-mentioned means for moving said shoe member includes a pair of bell-cranks pivotally connected to said supporting frame, said bell-cranks having one end operatively engaging and movable by said plate supporting said rollers, the other end of said bell-crank operatively engaging said shoe member, and resilient means normally urging said shoe member vertically downward.

References Cited in the file of this patent UNITED STATES PATENTS 2,630,959 Brown Mar. 10, 1953 2,732,991 De Bastos et a1. Jan. 31, 1956 2,758,434 Johnson Aug. 14, 1956 2,855,736 Harmon et a1. Oct. 14, 1958